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Vansant K.,LMS | Beriot H.,LMS | Bertolini C.,AUTONEUM | Miccoli G.,IMAMOTER
SAE International Journal of Engines

As the legislation for pass-by noise (PBN) has recently become more stringent, car manufacturers face again a challenging task to reach the new SPL objective (70dB(A)). A good design of the engine bay is therefore required to sufficiently attenuate the noise coming from sources as the engine and the intake. This involves proper design of the engine bay's panels including apertures, and a good selection of the type and location of acoustic treatments. For a given engine bay design, the PBN SPL results can be obtained with a PBN test or by an equivalent simulation. Using simulation models it is possible to create the perfect test environment virtually and moreover to obtain acoustic results for a large number of designs upfront of any actual testing or prototype. The challenge for simulation models is however that, as the results should typically be available from 20 Hz up to 4 or 5 kHz and overall SPL results should be retrieved from a narrow band response over this large frequency range, the CAE models required can become very large and many frequencies need to be computed resulting in long solving times. This paper will discuss on Boundary Element Method (BEM) and Finite Element Method (FEM) acoustic technologies available to predict powertrain exterior Acoustic Transfer Functions (ATFs) for a mock-up model of an engine bay. A comparison with Test results is provided to judge on the models' accuracy. Special focus is given to a comparative performance study for the different simulation approaches. Copyright © 2014 SAE International. Source

Ruggeri M.,IMAMOTER | Marani P.,IMAMOTER
SAE Technical Papers

The new X-by-Wire systems under study for commercial and heavy-duty vehicles, as well as for Agricultural Tractors, are increasingly real autonomous systems, capable to autonomously control a vehicle functionality, actuating the operator's commands, or managing in a complete autonomy a machine function. These application need an higher Performance Level from the functional safety point of view, due to the risk of a malfunction consequence. The paper deals with a new concept hydraulic spool valve that allow the design of new safer and more compacted hydraulic circuit architectures, ensuring higher safety performance levels. The architecture presents advantages both from performance (precision, fastness), both from operational point of view. The paper will focus in particular on safety and control topics. The new patented valve presents a secondary rotary type actuator connected to a sleeve interposed between the spool and the valve body, thus composing a roto-translating valve. The sleeve presents holes that can be moved and positioned partially or totally overlapped to the valve ports, thus allowing a secondary independent metering. The valve port area is then related to the movement of the spool, and to the rotary movement of the cylinder. The valve port area is the result of two actuators position, both controlled by a microcontroller based unit. Due to the valve structure, the metering control precision and valve speed are virtually quadratic in respect to the traditional valve spool position electronic control, due to the concurrency of two electronically controlled actuators. The valve can be configured to realize various control functions and, in terms of safety, it offers a fail operational characteristic, in reason of an operational redundancy and functional diversity. Copyright © 2014 SAE International. Source

Malaguti G.,IMAMOTER | Dian M.,IMAMOTER | Ruggeri M.,IMAMOTER
SAE Technical Papers

Ethernet is by now the most adopted bus for fast digital communications in many environments, from household entertainment, to PLC robotics in industrial assembly lines. Even in avionic applications, new standards are fixing research results. In a similar way in automotive industry, the interest in this technology is increasingly growing, pushed forward by much research and basically by the need of high throughput, that high dynamics distributed control requests. In the world of heavy-duty machines various needs suggest to investigate for a possible Ethernet Network implementation for both real time control and services. On the other hand Bosch proposes the FlexCAN, CAN Flexible rate, but it seems a short term solution for today's congested networks. Conversely, high speed cameras for assisted and indirect vision, virtual fencing systems, cooperative machines control suites, fleet management, task control aspects integration, and real time controls, are just some of the useful functions that could gain from a Ethernet based distributed control in heavy duty machines. This paper deals with architectural and technological aspects of advanced Ethernet networks in order to provide a high-throughput deterministic network for in-vehicle distribution control. Copyright © 2013 SAE International. Source

Ruggeri M.,IMAMOTER | Ferraresi C.,IMAMOTER | Dariz L.,IMAMOTER | Malaguti G.,IMAMOTER
SAE International Journal of Commercial Vehicles

Functional safety requirements and solutions are more expensive when it comes to lower cost machines with less power but same functionalities with respect to big machines. The paper will show a real Electronic Control Unit (ECU) design of a machine controller, controlling both engine working point, transmission, and other utilities like PTO, 4WD, brakes and Differential Lock; the ECU was designed in accordance to ISO 25119 regulation, to meet AgPL = C or even D for some functionalities. The unit is a fully redundant electronic control unit with two CAN networks and some special safe state oriented mechanism, that allow the Performance Level C with less software analysis requirements compared with traditional solutions. All safety critical sensors are redounded and singularly diagnosable, all command effects are directly observable and most of commands are directly diagnosable. With a minimum extra-cost the hardware category for the most critical controls was brought to the category 4, thus theoretically allowing the Performance Level D achievement. But the most unseen solution was to include this unit in the dashboard, thus creating a smart dashboard and machine controller, with an important machine cost reduction. The paper will explain all technical solution, analyzing functionalities and showing the most interesting problem solutions. The hazard analysis and the functional assessment results will be briefly exposed. Copyright © 2014 SAE International. Source

Malaguti G.,IMAMOTER | Ferraresi C.,IMAMOTER | Dariz L.,IMAMOTER | Ruggeri M.,IMAMOTER
SAE Technical Papers

Alongside with the increasing vehicle complexity, the functionalities related to the safety, diagnosis and maintainability have become critical. The operators of special machines such as agricultural, mining, construction vehicles might be overwhelmed by this increased complexity and, as a result, operations for the recovery or maintenance of their vehicles become difficult. The Augmented Reality (AR) seems to be a very promising technology both if applied to traditional smart-phones or to the upcoming glasses, that has been just presented to the market by several manufacturers. This paper reviews some use cases of applications created in Institute for Agricultural and Earthmoving Machines (IMAMOTER) of the National research Council of Italy (CNR) engineers laboratories, which propose a novel approach for assisted maintenance, recovery or training. These take advantage of the use of AR, providing an efficient method for user fast learning of simple procedures as well as a support for fault recovery and maintenance in hazardous environments or work places. In the first application scenario, the AR is used to recognize the dashboard and the machine controls in order to provide further information about them. In the second scenario the AR application is connected with a CAN-Bluetooth gateway to the SAE J1939 network and provides real-time information or messages in case of faults or anomalous conditions. Finally, a real implementation of AR technologies will be presented, that leads the user during recovery procedures, such a fuse replacement in three simple steps. The paper presents real Apps and future perspectives in the application of AR technology in Heavy-Duty vehicles. Copyright © 2014 SAE International. Source

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